With a small sharp knife, split vanilla bean down one side of the pod. Open up the pod and lay it flat on your cutting board. Using the back of your knife, remove the black seeds from the interior of the pod by scraping from one end of the open pod to the other. Place seeds and empty pod in a medium saucepan along with the pears, honey, cardamom, ginger and salt.
Cook over medium high heat, stirring frequently until the pears begin to break down and give up their liquid. Reduce the heat to low and continue to cook, stirring occasionally, until the pears are tender and the mixture is syrupy, about 20-30 minutes.
Remove the saucepan from the heat. Add lemon juice. Remove and discard the vanilla bean pod and ginger slices. Taste the mixture and season with additional lemon juice, salt or honey to taste. Once the compote has cooled, transfer to a clean jar and store in the refrigerator for up to one week. Freeze for longer storage.